Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The FHIT (fragile histidine triad) gene on chromosome 3p14 is a candidate tumor suppressor gene, and its transcripts are shown to be abnormal in several human cancers. We examined 40 leukemia samples for the alterations of FHIT transcripts by reverse transcriptase-polymerase chain reaction (RT-PCR) and direct sequencing. Intact FHIT mRNA was not detected in two patients with acute myeloid leukemia (AML) and in one patient with chronic lymphocytic leukemia (CLL). The three cases expressed only an aberrant FHIT mRNA lacking exons 3 to 6 (FHIT delta 3-6 mRNA), which could encode a polypeptide of 13 amino acids. Southern blot analysis on two samples from these cases showed no rearrangements of the FHIT gene. Although intact FHIT mRNA was detected as the main band in the remaining 37 samples, 33 of them (14 of 14 AML, 11 of 13 chronic myeloid leukemia, five of five acute lymphocytic leukemia, and three of five CLL) expressed aberrant FHIT delta 3-6 mRNA. We barely detected the FHIT delta 3-6 mRNA in only one of 25 normal control samples. Our results suggest that loss of the normal FHIT function may be involved in the genesis of at least some human leukemias and that expression of aberrant FHIT transcripts is rather specific and frequent in leukemia samples.
 ...
PMID:Decreased or altered expression of the FHIT gene in human leukemias. 917 Feb 14

Aberrant FHIT mRNA transcripts are present in malignant and normal haematopoiesis, but absence of FHIT protein is restricted to leukaemia Alterations of the recently cloned fragile histidine triad (FHIT) gene at chromosome 3p14.2 are frequent in a variety of solid tumours and cancer cell lines. Based on these findings, FHIT has been proposed as a putative tumour-suppressor gene. We evaluated the mRNA expression of the FHIT gene in samples from 55 patients with various haematological malignancies (21 AML, 8 CML, 10 CLL, seven low-grade and nine high-grade Non-Hodgkin's lymphomas), in a panel of 16 leukaemia cell lines, in normal mature haematopoietic cells of both myeloid and lymphoid lineage, as well as in CD34+ haematopoietic progenitor cells. Aberrant FHIT mRNA transcripts were observed in 14/16 (88%) leukaemia cell lines, 43/55 (78%) primary haematological neoplasms, but also in 17/22 (77%) normal controls. 1/16 (6%) cell lines and 7/55 (13%) neoplasms did not express any FHIT mRNA. cDNA sequencing revealed exonic deletions, small DNA insertions and combinations of both. Analysis of genomic DNA showed gene deletions in two myeloid leukaemia cell lines. In contrast to all normal types of haematopoietic cells, FHIT protein was clearly reduced or absent in 8/18 (44%) neoplastic samples tested. Our data indicate that whilst aberrant FHIT mRNA transcripts are seen both in normal and malignant cells, lack of FHIT protein is restricted to leukaemia. Absent FHIT protein expression might contribute to leukaemogenesis.
 ...
PMID:Aberrant FHIT mRNA transcripts are present in malignant and normal haematopoiesis, but absence of FHIT protein is restricted to leukaemia. 992 22

Loss or reduced expression of the fragile histidine triad (FHIT) gene, a tumor suppressor gene localized at chromosome 3p14.2, is common in several solid and hematological cancers and has been associated with tumor progression and worse prognosis. The role of the FHIT gene in the pathogenesis of chronic myelogenous leukemia (CML) or its progression from a chronic phase to the accelerated and blastic phases is not known. The aim of this study was to evaluate whether Fhit protein expression is altered in CML, and whether it plays any role in CML progression, disease responsiveness to therapy, or prognosis. A total of 195 patients with Philadelphia chromosome-positive CML were evaluated, including 129 patients in early chronic phase (time from diagnosis to study, 12 months or less), 30 patients in late chronic phase, and 36 patients in the accelerated and blastic phases. The levels of cellular Fhit protein expression were determined using Western blot analysis and solid-phase RIA and compared to the levels in 31 normal marrows. The median Fhit expression in normal marrows was assigned a value of 1, and the levels in CML samples were normalized to the median of the normal control. Fhit levels in CML samples were evaluated in relation to CML phase and patient characteristics and prognosis in the early chronic phase. The median Fhit value in CML samples was 0.89 (range, 0.34-2.62). Eight of the 195 (4%) CML samples showed Fhit levels <0.5 and lacked detectable Fhit protein by Western blot. There was no difference in the levels of Fhit expression by different CML phases. In early chronic phase, reduced Fhit expression tended to be associated with leukocytosis (P = 0.04) and lower platelet counts (P = 0.01), but not with poorer-risk groups. No differences in response to IFN-alpha therapy or in survival were observed by different Fhit levels. Lack of Fhit protein expression was detected in 4% of CML cases, and reduced expression occurred in a subpopulation of patients. However, reduced Fhit expression is not associated with progression, response to therapy, or prognosis in CML.
 ...
PMID:Significance of FHIT expression in chronic myelogenous leukemia. 1063 40

FHIT (fragile histidine triad) gene at chromosome 3p14.2 usually expresses at a very low level in human tissue and cells. A high frequency of abnormalities in FHIT gene has been demonstrated in various cancers. FHIT is proposed as a putative tumor-suppressor gene. To evaluate the expression of the FHIT gene in various leukemias, bone marrow or peripheral blood samples from 98 leukemia patients were tested by RT-PCR: 38 from patients with AML-[M(2)(9), M(3)(12), M(4)(8), M(5)(9)], 16 with ALL, and 34 with CML-[CP(20), AP(4), BC(10)] of various FAB types, as well as 10 patients with other hematological malignancies. To detect a deletion in sequencing the FHIT gene, the representative aberrant PCR products were cloned and then sequenced. The results showed that 22/38 (58%) patients with AML, 9/16 (56%) patients with ALL and 19/34 (56%) patients with CML were detectable of aberrant FHIT mRNA transcripts or deletion of FHIT. In 6 (16%) AML patients, 3 (19%) ALL patients, and 5 (15%) CML patients, the wild-type product was absent. Some patient's samples - 6 (42%) AML, 6 (38%) ALL, and 14 (41%) CML revealed aberrant FHIT transcripts in addition to a normal-sized band. Samples from healthy donors (PB, n = 12; BM, n = 5) did not indicate any abnormal expression. Eleven isolated fragments from various patterns of FHIT gene expression were investigated using cDNA sequencing. Sequence analysis revealed deletion of exon 4-8, exon 5-8, and exon 5-6 in various leukemias, as well as the deletion of the full FHIT gene sequence. The fused transcripts included: exon 3 and exon 9, exon 3 and exon 7, exon 4 and exon 9, exon 5 and exon 7. Sequence analysis of aberrant fragments present in samples from an AML and a CML patients was detected for point mutations and insert mutations located in exons 2, 8 and 10, plus a variety of aberrant transcripts. Deletion or aberrant FHIT mRNA transcripts in 50/98 (51%) leukemia patients were found. All samples with aberrant FHIT lacked gene product. A Kaplan-Meier plot of survival in patients with AML in relation to FHIT expression revealed that aberrance or loss of FHIT gene significantly correlated with a low clinical remission rate and poor overall survival.
 ...
PMID:Aberrant expression and deletion of FHIT gene in leukemias. 1274 37